Terry Collins #10 manager of the New York Mets looks on from the dugout before a baseball game against the San Diego Padres at PETCO Park on May 5, 2016 in San Diego, California. (Credit: Getty Images/ Denis Poroy)

DENVER — By sight alone, Terry Collins looked comfortable behind the desk in the visitors manager’s office here. But before Friday night’s series opener against the Rockies, he made it clear that he’s glad that the Mets come through town only once a season.

“For me, it’s not a great place to manage,” said Collins, not a fan of the high elevation and thin air that can clobber pitching-heavy teams such as the Mets. “It’s not for [pitching coach] Dan Warthen, he doesn’t have much fun here. [Hitting coach] Kevin Long was the first guy at the park here.”

Collins sounded bemused at what seemed to be a daunting chore in the extreme elevation: getting his pitchers mentally tough enough to deal with the constant disadvantage while keeping his hitters from developing bad habits and a false sense of security.

In the past, Collins said he has watched hitters fall in love with swinging for the fences, lapsing into uppercut swings that can mean big numbers in the elevation and big headaches everywhere else.

“That is something that is going to be addressed here,” Collins said before the Mets huddled for their typical hitters’ meeting before the first game of every series. “Listen, it’s not about trying to hit homers. It’s about squaring the ball up. Homers happen.”

When asked if he must manage the bullpen differently because of the increased chance of a high-scoring game, Collins answered: “You hope they answer the phone. It’s one of the biggest things. A lot of times, they don’t.”

When asked if he must adjust the way the Mets shift in the field, Collins said: “The fence keeps you from going too far. You have to stay on this side. I’d be in the third row if I could put somebody out there.”

Though Collins had fun with his qualms about Coors Field, the environment has proven to be no laughing matter. The Mets entered their series opener Friday night with four straight victories here, but they are just 9-15 in Colorado since 2009.

Collins cut his teeth as a minor-league manager in the Pacific Coast League, home to several notoriously hitter-friendly locales at high elevation. It’s a fact that visitors to Coors Field are reminded by simply looking up. A purple row of seats rings the top of the ballpark marking one mile above sea level.

Oftentimes, Collins said, it’s not the tape-measure home runs that do the most damage. It is instead the paper cuts — bloop hits falling in front of outfielders — that can accumulate and wreck a pitcher’s night.

“Everybody talks about the ball flying here,” Collins said. “All the years I spent in this — not only in Colorado Springs and Albuquerque and all those other places where the ball flies — it’s the bloop singles that kill you as much as the home run. It’s a big park, the outfielders play deep because of the ball going over their head, and the next thing you know, balls are dropping in all over. That is the area where these parks do damage.”

But pitching well in Denver is not impossible. Consider Logan Verrett, the Mets’ reliever who is making a spot start Saturday in place of the banged-up Steven Matz. Last August, in a similar spot, Verrett stepped in for Matt Harvey and held the Rockies to just one run in eight innings.

“It’s all the mental part,” Warthen said. “You’re going to give up some hits. You’re going to give up some home runs. Don’t walk anybody. Try to make them solo home runs.”